1. Field of the Invention
The present invention relates to a method of treating ore for improving the quality of an ore containing an oxide of a useful element, and particularly, to an ore treating method for treating an ore used in iron and steel manufacturing, an ore treating apparatus, an iron manufacturing method, and an iron and steel manufacturing method.
2. Description of Related Art
A process of producing pig iron from iron ore using a blast furnace is a process often used in an iron manufacturing method. A blast furnace is a structure nearly in the form of cylinder having an internal surface constituted of a refractory body, and in operation of a blast furnace, iron ore and coke as raw materials are charged in the form of layer from an upper part thereof and air heated at high temperature is blown through a blast tuyere provided at a lower part of the blast furnace. In blowing air through a blast tuyere, powdered coal is simultaneously blown in many cases. Iron oxide contained in iron ore is reduced over a long period of time by carbon monoxide generated by combustion of coke and powdered coal and gasification with carbon dioxide and melted, to give a hot metal which is then discharged from a lower part of the blast furnace. Though carbon contained in coke and powdered coal acts as a reducing agent, the distance between carbon and iron oxide is in the order of several centimeters and thus a direct reduction as an inter-solid reaction of carbon and iron oxide does not occur in the blast furnace, resulting mainly in an indirect reduction with a carbon monoxide gas. As described above, the current iron manufacturing industry utilizes, as carbon sources, coke and powdered coal derived from mineral coal as a fossil resource.
On the other hand, there is sought utilization of organic wastes or biomass resources for suppressing consumption of fossil resources from the standpoint of prevention of global warming-up. The biomass resources include organic substances derived from living organisms excluding fossil resources and have a so-called carbon neutral feature wherein the discharge amount of carbon dioxide including a combination of two stages of production and consumption is approximately zero. A trial is made in which these organic wastes or biomass resources are dry-distilled and a gas generated by dry distillation is utilized as an energy source. There is a problem, however, in which the produced gas includes organic compounds such as tar and the like which are liquid of high viscosity at normal temperature, and, in cooling of the gas, the organic compounds such as tar and the like liquefy and adhere to internal surfaces of the furnace, piping and the like, thereby generating a gas continuously. Japanese Patent Application Laid-Open (JP-A) No. 2001-327861 discloses a technology of adsorbing tar onto a ceramic containing alumina, silicon dioxide and the like as a component, for removing tar components from a gas.